@article{ref1,
title="Method and application of grade division for road traffic congestion based on driver's feeling",
journal="Advances in mechanical engineering",
year="2015",
author="Qi, Weiwei and Wen, Huiying and Wu, Yaping",
volume="7",
number="11",
pages="e1687814015618860-e1687814015618860",
abstract="<p>[Abstract unavailable]</p> <p>Language: en</p>",
language="en",
issn="1687-8132",
doi="10.1177/1687814015618860",
url="http://dx.doi.org/10.1177/1687814015618860"
}